KR101466703B1 - Wideband tunable vertical-cavity surface-emitting laser - Google Patents

Abstract

Surface-emitting laser is used as a light source for short/middle distance communications and utilization in an optical connection, an optical sensor, and an optical communication is rapidly increased. Particularly, the necessity of the optical communication and the optical connection using a light source of various wavelengths like CWDM and DWDM is recently increased to transmit and process big data. Besides, Use in a 3D scan for detecting the defect of the surface and the feature analysis of a device of a wavelength feature using a wavelength control feature is increased. For an application like this, a continuous wavelength control without a discontinuous wavelength in a middle part and the wavelength control of the broadband like 100 nm are necessary. The present invention relates to the wideband tunable vertical-cavity surface-emitting laser in all wavelength regions capable of controlling the oscillation wavelength of the wideband by controlling a resonant distance using an air gap formed between a top mirror layer and an active layer after forming a dielectric mirror layer with a wide stop band on the top mirror layer and a bottom mirror layer. The present invention provides the wideband tunable vertical-cavity surface-emitting laser capable of performing the continuous control of the wideband.

Description

Wideband tunable vertical-cavity surface-emitting laser [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadband wavelength-tunable surface emitting laser, and more particularly to a wavelength tunable surface emitting laser having a dielectric mirror layer and a metal mirror layer together as a lower mirror layer so that a substrate can be partially removed, And a resonance distance between the upper mirror layer and the active layer due to the voltage is adjusted to control the oscillation wavelength.

Surface emitting lasers are used as light sources for short / medium distance communication, and their use in optical connection, optical sensor and optical communication is increasing rapidly. In particular, the high fiber-coupling efficiency of a surface emitting laser, low unit cost due to wafer-based fabrication processes, low mounting cost, low electrical power consumption, a two-dimensional array array characteristics, it is expected to quickly become a light source for next generation optical communication and signal processing.

Recently, there is an increasing need for optical connection and optical communication using light sources of various wavelengths such as CWDM (Coarse Wavelength Division Multiplex) and DWDM (Dense Wavelength Division Multiplex) for large data processing and transmission. If a light source using one wavelength is used, a method of increasing the modulation speed of the optical connection and the optical communication light source should be used in order to increase the capacity. However, in this case, there is a limit to improve the speed and the connection and transmission distance There are disadvantages.

Therefore, when optical connection and optical communication of various wavelengths are used, it is possible to increase the transmission rate of each wavelength and the capacity by increasing the channel, thereby enabling transmission and processing of a large capacity signal over a long distance. However, since an individual light source having respective wavelength characteristics must be manufactured and applied for optical connection and optical communication using various wavelengths, it is difficult to manufacture a light source having respective wavelengths, and it is difficult to raise or replace the light source.

In addition, since the wavelength is fixed in the configuration of the whole network, there is a disadvantage that a flexible network is not formed.

In order to overcome such disadvantages, it is necessary to provide a light source having various wavelength characteristics by controlling the wavelength as one light source.

In addition, the use of wavelength tuning characteristics has been expanding the use of devices such as wavelength-characteristic device analysis and three-dimensional scanning to detect surface defects. For such applications, Continuous wavelength control without discontinuous wavelength is needed in the middle.

This characteristic is difficult to obtain by adjusting the current of an edge-emitting laser, and therefore, it is desired to provide a wavelength-tunable surface emitting laser capable of continuously controlling a wide band in the present invention.

The wavelength tuning surface emitting laser is mainly formed by forming a thin air layer by partially etching between the thin upper mirror layer and the upper current injection layer and adjusting the space of the mirror layer and the active layer by applying a voltage therebetween, . When the wavelength is controlled, the bandwidth is determined by the width of the stop band of the upper and lower mirror layers, the width of the gain of the active layer, and the adjustment width of the resonance distance. Particularly, the width of the stop band of the upper and lower mirror layers is a main characteristic for determining the bandwidth since it has a limit according to the constituent materials.

In the conventional wavelength tuning surface emitting laser, a dielectric mirror layer or the like is used for the 850 nm band of GaAs (GaAs) substrate and a dielectric mirror layer is used for the upper mirror. The lower mirror layer is made of Al _x Ga _{1 - x} As / Al _y Ga _{1 - y} As (0 < x, y < 1).

However, using the difference of the composition, the maximum stop band width is 80 nm, and the wavelength tuning width is about 60 nm. In order to widen the stop band of the lower mirror layer, the semiconductor DBR of the lower mirror layer is composed of Al _x Ga _{1 - x} As / Al _y Ga _{1 - y} As (0 < x, y < 1) And a mirror layer of Al _x Ga _{1 - x} As / Al _y Ga _{1 - y} O _x (0 < x, y < 1) is used as the Al _y Ga _{1 - y} As, . In such a case, the stop band has an advantage that it can obtain 200 nm or more, but the process for forming the oxide film of the lower mirror layer is complicated and the stress due to the oxide film is weighted on the substrate.

In addition, the lower mirror layer by, for example, when the longer wavelength of 1310nm or more bands of InP (indium phosphide) substrate than the 850nm band, removing the substrate and wafer bonded _{Al x Ga 1 - x As /} Al y Ga 1-y As (0 <x , y < 1), the composition of y is made close to 1, and Al _y Ga _{1 - y} As is formed as an oxide film to form Al _x Ga _{1 - x} As / Al _y Ga _{1 - y} O _x (0 < x, y < 1). This is a disadvantage of complicated fabrication process due to addition of processes such as wafer bonding in addition to oxide film formation.

The present invention provides a broadband wavelength-tunable surface emitting laser applicable to a wavelength band of 850 to 1550 nm by forming a lower mirror layer together with a dielectric mirror layer and a metal mirror layer so as to partially remove a substrate and have a reflectance at a wide wavelength.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a dielectric mirror and a metal mirror layer together as a lower mirror layer so as to partially remove a substrate and have a reflectance at a wide wavelength, To adjust the resonance distance of the laser to adjust the oscillation wavelength, thereby providing a broadband wavelength-tunable surface emitting laser in various wavelength ranges.

According to the present invention, an air gap is formed between an upper mirror layer and an active layer, and a voltage between the upper mirror layer and the active layer is adjusted to control a distance between the upper mirror layer and the active layer, And a portion of the substrate is removed to form a lower mirror layer composed of a dielectric mirror layer and a metal mirror to form a stop band of reflectance in a wide band region to provide a broadband wavelength tuning surface emitting laser capable of adjusting a wavelength in a wide wavelength band .

More specifically, the present invention relates to a broadband wavelength tuning surface emitting laser element comprising: an etching resistance layer and a lower cladding layer sequentially stacked on a semiconductor substrate; a gain layer for gain on the lower cladding layer; Forming an upper cladding layer, an etching layer on the upper cladding layer, and a supporting layer composed of a semiconductor doped on the etching layer, sequentially forming an upper dielectric mirror layer on the supporting layer, An electrode for voltage application is formed and a part of the casting layer is selectively removed to form an air gap between the active layer made of the lower clad layer, the gain layer and the upper clad layer and the supporting layer, An electrode for voltage application is formed, a part of the lower part of the substrate is removed, the etching resistant layer is continuously removed A lower dielectric mirror layer is formed, and a metal mirror layer is formed below the lower dielectric mirror layer. A lower mirror layer composed of an upper mirror layer and an upper layer consisting of an upper dielectric mirror layer and a supporting layer, and an active layer and a mirror layer composed of a lower dielectric mirror layer and a metal mirror layer form a resonator to emit laser light. The distance of the air gap is controlled, and the resonance distance is changed between the upper mirror layer, the active layer, and the lower mirror layer, so that the oscillation wavelength can be adjusted. An upper mirror layer composed of an upper dielectric mirror layer and a supporting layer, and a lower mirror layer composed of a lower dielectric mirror layer and a metal mirror layer are configured to have a stop band of 100 nm or more for adjusting a broadband wavelength.

In a preferred embodiment, the upper and lower dielectric mirror layers are made of a material having a large dielectric constant such as SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si, CaF2 / ZnS, The length divided by the refractive index) is made to be two to seven cycles in one cycle. The metal mirror layer is formed by depositing a metal such as Au, Al, or Ag.

The broadband wavelength-tuned surface emitting laser of the present invention is formed by forming a dielectric mirror layer having a wide stop band on the upper and lower mirror layers and using an air gap formed between the upper mirror layer and the active layer, The present invention relates to a surface emitting laser, and more particularly, to a method of fabricating a broadband wavelength tunable surface emitting laser device in all wavelength regions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a broadband wavelength-tunable surface emitting laser according to an embodiment of the present invention;
FIG. 2 and FIG. 3 each show a cross-sectional structure and an upper structure of a broadband wavelength-tunable surface emitting laser according to another embodiment of the present invention,
4 is a graph showing the stop band characteristics of the lower mirror layer of the broadband wavelength-tunable surface emitting laser of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, in order to facilitate a person skilled in the art to easily carry out the technical idea of the present invention. do.

1 shows a cross-sectional view of a broadband wavelength tunable surface emitting laser structure according to a preferred embodiment of the present invention. In the figure, reference numeral 21 denotes a semiconductor substrate, 22 denotes an etching resistant layer composed of a semiconductor, 23 denotes a lower clad layer composed of a semiconductor, 24 denotes a gain layer composed of a multilayer quantum well for imparting gain, 25 denotes an upper clad layer Reference numeral 28 denotes an upper electrode for voltage driving, reference numeral 29 denotes an upper mirror electrode for voltage driving, reference numeral 30 denotes an upper dielectric mirror layer for constituting the upper mirror layer, reference numeral 30 denotes an upper dielectric mirror layer, A lower dielectric mirror layer for constituting the lower mirror layer, 32 a lower metal mirror layer for constituting the lower mirror layer, and 33 an air gap for adjusting the resonance distance.

In this embodiment, a voltage is applied between the upper mirror electrode 29 and the upper electrode 28 to control the distance of the air gap 33. When the light generated in the gain layer 24 is incident on the upper dielectric mirror layer 30, The support layer 27, the air gap 33, the upper clad layer 25, the gain layer 24, the lower clad layer 23, the lower dielectric mirror layer 31, and the metal mirror layer 32 And emits laser light.

At this time, the resonance distance is changed according to the distance of the air gap 33, and the oscillation wavelength is adjusted. The tuning band of the wavelength is determined by the stop band of the upper dielectric mirror layer 30 and the lower dielectric mirror layer 31 and the metal mirror layer 32. The upper dielectric mirror layer 30 and the lower dielectric mirror The layer 31 is made of a material having a large dielectric constant difference such as SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si, CaF2 / ZnS etc. so that the thickness thereof becomes 0.25x optical length (length divided by the refractive index at the center wavelength) And two layers constituted by two layers are formed in one cycle and about two to seven cycles are formed. The metal mirror layer 32 is formed by depositing a metal such as Au, Al, or Ag. Accordingly, the oscillation wavelength can be adjusted to a wide band of 100 nm or more.

2 illustrates a cross-sectional view of a broadband wavelength tunable surface emitting laser structure according to another embodiment of the present invention. Fig. 3 shows the superstructure of the broadband wavelength-tunable surface emitting laser structure shown in Fig.

A gain layer 44 for gain is formed on the lower clad layer 43 and a lower clad layer 43 is formed on the upper clad layer 43. The lower clad layer 43 is formed on the semiconductor substrate 41, An upper cladding layer 45 made of a semiconductor doped on the gain layer 44, a current confining layer 46 on the upper cladding layer 45, and a semiconductor doped on the current confining layer 46 An upper etching resistance layer 47, an etching layer 48 on the upper etching resistance layer 47 and a supporting layer 49 composed of a semiconductor doped on the etching layer 48 are successively formed, 49 and an upper mirror electrode 52 for applying a voltage to the other upper portion of the supporting layer 49. The supporting layer 49 and the etching layer 48 are formed on the upper dielectric mirror layer 51, The upper etching resistance layer 47, the current confining layer 46, the upper cladding layer 45, and the gain layer 44 are etched and then the current limiting A part of the etching layer 46 is selectively etched and then an insulating layer 50 filled with an insulating material is formed and a part of the etching layer 48 is selectively removed to form an upper etching resistance layer 47 and a supporting layer 49 Forming an air gap 55 between the lower dielectric mirror layer 53 and the lower dielectric mirror layer 53 to remove a portion of the lower portion of the semiconductor substrate 41 and successively removing the etch resistant layer 42, A metal mirror layer (54) is formed under the dielectric mirror layer (53). A lower electrode insulating layer 61 for insulation is formed on a part of the lower clad layer 43 and a part of the upper clad layer 43 and a lower part of the lower electrode insulating layer 61 Electrode 62 is formed. An upper electrode insulating layer 63 for insulation is formed on a part of the lower clad layer 43 and a part of the upper etching resistance layer 47 and a part of the upper electrode insulating layer 63 The upper electrode 64 is formed.

The upper dielectric mirror layer 51 and the lower dielectric mirror layer 53 are formed of SiOx / SiNx, SiOx / SiNx, and SiOx / SiNx, respectively, by selectively depositing AlOx or AlNx by ALD (atomic layer deposition) The thickness of each layer is 0.25x optical length (length divided by the refractive index), such as TiOx, CaF2 / a-Si, CaF2 / ZnS, And the metal mirror layer 54 is formed by depositing a metal such as Au, Al, Ag, or the like to have a stop band of 100 nm or more.

A current is applied between the upper electrode 64 and the lower electrode 62 to flow a current into the gain layer 44 without the insulating layer 50 to form light and the formed light passes through the resonance 57 in the resonator. And the upper dielectric mirror layer 51 and the support layer 49 are displaced by applying a voltage between the upper mirror electrode 52 and the upper electrode 64. As a result, (Indicated by arrows 56), the distance of the air gap 55 is changed, and the resonance distance is adjusted to change the oscillation wavelength, thereby obtaining the characteristic of the broadband wavelength-tuned surface emitting laser.

4 is a graph showing the reflectance characteristics of the lower dielectric mirror layers 31 and 53 and the metal mirror layers 32 and 54 in the laser device of the embodiment shown in FIGS. 1 and 2 by AlAs / GaAs, AlOx / GaAs DBR And the reflectance of the mirror layer. In the structure of the lower dielectric mirror layers 31 and 53 and the metal mirror layers 32 and 54 in the embodiment of the present invention, the stop band has a broadband reflection characteristic of 230 nm. In the case of the AlAs / GaAs DBR mirror layer, the stop band is about 80 nm, which is not suitable as a broadband wavelength tuning mirror layer. The AlOx / GaAs DBR mirror layer has the widest stop band characteristic, Lt; / RTI &gt;

The preferred embodiments of the present invention will be described in more detail with reference to FIGS. 2 and 3. FIG.

On the InP semiconductor substrate 41 as an etching resist layer _{(42) In y (Al x} Ga 1 -x) 1- y As (0 <x, y <1) or _{In x Ga 1 - x As y} P 1 -y (0 <x, y <1 ) , etc. is formed and in, that an over-doped in nearly lattice matched to the structure of InP or InP doped with a lower cladding layer _{(43) in x Ga 1 -} x as y P 1 -y (0 <x, y <1 ) is formed in the lower clad layer 43 is formed on the _{in y (Al x Ga 1 -x} ) 1-y as / in z (Al w Ga 1 -w) such as _{1- z} A gain layer 44 composed of As (0 < x, y, z, w < 1) quantum well layers is formed. Consisting of _{x As y P 1 -y (0} <x, y <1) including an upper cladding layer (45), _- the gain-doped InP layer or In _x Ga ₁ for the protection at 44 formed on the current diffusion and selectively etching Doped In _y (Al _x Ga _{1 -x} ) _{1 -y} As (0 < x, y < 1) or In _x Ga _{1 - x} As _{y P 1 -y (0 <x} , y <1) current limiting layer 46, formed on the current confining layer 46 is doped to the upper electrode contacts, and upon selectively etching protective InP or in _x Ga ₁ consisting of _{- x as y P 1 -y (0 <} x, y <1) etching the upper resistance layer (47), in _y (Al _x Ga _{1 -x)} on the top etch resistant layer 47 consisting of such as _{1- y} as (0 <x, y <1 ) or _{in x Ga 1-x as y} P 1-y (0 <x, y <1) type layers 48 formed with such doped on the type layers 48 A supporting layer 49 composed of InP or In _x Ga _{1 -x} As _y P _1-y (0 < x, y < 1) is sequentially formed on the supporting layer 49. SiOx / SiNx, SiOx / TiOx, CaF 2 / a-Si, CaF2 / ZnS, and the like, each having a thickness of 0.25x optical length (a length obtained by dividing the center wavelength by the refractive index) Ti / Au / Au / Ni / Au, Ti / Au, and Cr / Au for applying a voltage to the other upper portion of the support layer 49. The upper dielectric mirror layer 51 The upper mirror electrode 52 is formed and the supporting layer 49, the etching layer 48, the upper etching resistance layer 47, the current confining layer 46, the upper cladding layer 45, the gain layer 44, A part of the current confining layer 46 for current limitation is etched by selective etching, and then the etched portion is etched by AlO _x or AlN _x And an insulating layer 50 filled with an insulating material such as AlO _x formed by an oxidation method is formed on the insulating layer 50. A part of the insulating layer 48 is formed of phosphoric acid or sulfuric acid or a mixture thereof An air gap 55 is formed between the upper etching resistance layer 47 and the supporting layer 49 and a part of the lower portion of the substrate 41 is removed and the etching resistance layer 42 is continuously (SiO 2 / SiN x), SiO x / TiO x, CaF 2 / a-Si, CaF 2 / ZnS and the like, each of which has a thickness of 0.25 × optical length (length divided by the refractive index) And a metal such as Au, Al, Ag, or the like is deposited on the lower dielectric mirror layer 53 to form a lower dielectric mirror layer 53, A mirror layer 54 is formed. A lower electrode insulating layer 61 such as SiNx or SiOx for insulation is formed on a part of the upper clad layer 43 and a part of the upper clad layer 43 and the lower electrode insulating layer 61 A lower electrode 62 composed of Ti / PT / Au, AuGe / Ni / Au, Ti / Au, Cr / An upper electrode insulating layer 63 such as SiNx or SiOx for insulation is formed on a part of the lower clad layer 43 and a part of the upper upper electrode insulating layer 47, An upper electrode 64 made of Ti / PT / Au, AuGe / Ni / Au, Ti / Au, or Cr / Au is formed on a part of the upper electrode 63. An electric current is applied between the upper electrode 64 and the lower electrode 62 to cause current to flow into the gain layer 44 without the insulating layer 50 to generate light and the generated light is resonated in the resonator 57 The laser beam 58 is emitted and a voltage is applied between the upper mirror electrode 52 and the upper electrode 64 to cause the upper dielectric mirror layer 51 and the support layer 49 to displace 56 The distance of the air gap 55 is changed, and the resonance distance is adjusted to change the oscillation wavelength, so that the characteristic of the broadband wavelength tuning surface emitting laser is obtained.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. In addition, it will be understood by those of ordinary skill in the art that various embodiments are possible within the scope of the technical idea of the present invention.

21: semiconductor substrate 22: etching resistant layer
23: lower clad layer 24: gain layer
25: upper clad layer 26:
27: support layer 28: upper electrode
29: upper mirror electrode 30: upper dielectric mirror layer
31: lower dielectric mirror layer 32: metal mirror layer
33: air gap 41: semiconductor substrate
42: etch resistant layer 43: lower clad layer
44: gain layer 45: upper cladding layer
46: current limiting layer 47: upper etching resistant layer
48: expression layer 49: support layer
50: insulating layer 51: upper dielectric mirror layer
52: upper mirror electrode 53: lower dielectric mirror layer
54: metal mirror layer 55: air gap
56: displacement of support layer and upper dielectric mirror layer
57: resonance of light 58: emission of light

Claims (11)

An upper cladding layer made of a semiconductor doped on the gain layer; a current confinement layer on the upper cladding layer; a current confinement layer on the lower cladding layer; An upper etching resistant layer made of a semiconductor doped on the upper layer, an etching layer on the upper etching resistance layer, and a supporting layer composed of a semiconductor doped on the etching layer are sequentially formed, and an upper dielectric mirror layer is formed on a part of the supporting layer An upper mirror electrode for applying a voltage to another upper portion of the supporting layer, etching a part of the supporting layer, the etching layer, the upper etching resistance layer, the current confining layer, the upper clad layer and the gain layer, A part of the confinement layer is selectively etched to form an insulating layer filled with an insulating material, and a part of the etching layer is selectively removed Forming an air gap between the upper etch stop layer and the support layer, removing a portion of the lower portion of the semiconductor substrate, continuously removing the etch stop layer, forming a lower dielectric mirror layer, Forming a metal mirror layer, forming a lower electrode insulating layer for insulation on a part of the lower clad layer, forming a lower electrode on a part of the lower clad layer and a part of the lower electrode insulating layer, Forming an upper electrode insulating layer for insulation on a part of the upper layer and forming an upper electrode on a part of the upper etching resistance layer and a part of the upper electrode insulating layer. A current is applied between the upper electrode and the lower electrode to cause current to flow into the gain layer without an insulating layer to form light, and the formed light resonates in the resonator to emit laser light, And the upper dielectric mirror layer and the supporting layer are displaced by applying a voltage between the upper dielectric layer and the upper electrode to change the air gap distance, and the resonance distance is adjusted to change the oscillation wavelength.
The method according to claim 1,
Wherein the insulating layer is formed by selectively etching the current confined layer and then depositing AlOx or AlNx by ALD (atomic layer deposition).
The method according to claim 1,
The upper dielectric mirror layer is made of a material having a large difference in dielectric constant including SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si and CaF2 / ZnS, each having a thickness of 0.25x optical length (length divided by the refractive index at the center wavelength) Wherein the wavelength of the laser light is set so that two to seven periods are formed in one cycle.
The method according to claim 1,
The lower dielectric mirror layer is made of a material having a large difference in dielectric constant including SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si and CaF2 / ZnS. Each of the lower dielectric mirror layers has a thickness of 0.25x (length divided by refractive index) Wherein the wavelength of the laser light is set to be 2 to 7 cycles in one cycle.
The method according to claim 1,
Wherein the metal mirror layer is formed by depositing any one of Au, Al, and Ag.
As the etching resist layer on the InP semiconductor substrate _{In y (Al x Ga 1 -x} ) 1- y As (0 <x, y <1) or _{In x Ga 1 - x As y} P 1 -y (0 <x, y <1) is formed in a or the like, that the over-doped in the lattice-matched to InP or InP doped structure as the lower cladding layer in _x Ga _{1 -} a _{x as y P 1 -y (0} <x, y <1) is formed, on the lower cladding layer of _{in y (Al x Ga 1 -x} ) 1- y As / in z (Al w Ga 1 -w) 1-z As s (0 <x, y, z, w <1) both of the gain layer consisting of a well layer is formed, and doped on the gain of the InP layer or in _x Ga _{1 -} consisting of _{x as y P 1 -y (0} <x, y <1) upper cladding layer, doped on the upper cladding layer _{in y (Al x Ga 1 -x} ) 1-y As (0 <x, y <1) or _{in x Ga 1 - x As y} P 1 -y (0 <x , y <1) current confined layer, a doped layer formed on the current limit of InP or in _x Ga ₁ consisting of _{- x} as _y P _{1 -y} (upper etching resist layer consisting of 0 <x, y <1) , the the etching of the upper resist layer (47) in _y (Al _{x Ga 1 -x) 1- y As} (0 <x, y <1) or In _x Ga _{1 -} type layers formed of a _{x As y P 1 -y (0} <x, y <1), each layer of the formula the InP or in _x Ga ₁ doped to the _{phase-in x as y P 1 -y (0} <x, y <1) , and forming a support layer are sequentially configured, and forming a top dielectric mirror layer composed of a portion above the support layer Forming an upper mirror electrode for applying a voltage to another upper portion of the supporting layer, etching the supporting layer, the etching layer, the upper etching resistance layer, the current confining layer, the upper clad layer and the gain layer, A portion of the etching layer is selectively etched to form an air gap between the upper etching resistant layer and the supporting layer, A part of the lower part of the substrate is removed, the etching resistant layer is successively removed, A metal mirror layer is formed on the lower part of the lower dielectric mirror layer, a lower electrode insulating layer is formed of SiNx or SiOx for insulation on a part of the upper clad layer and a part of the upper clad layer Forming a lower electrode on a part of the lower electrode insulating layer, forming an upper electrode insulating layer of SiNx or SiOx for insulation on a part of an upper surface of the lower clad layer, And forming an upper electrode on a part of the layer. A current is applied between the upper electrode and the lower electrode to cause current to flow into the gain layer without an insulating layer to form light, and the formed light resonates in the resonator to emit laser light, And the upper dielectric mirror layer and the supporting layer are displaced by applying a voltage between the upper dielectric layer and the upper electrode to change the air gap distance, and the resonance distance is adjusted to change the oscillation wavelength.
The method of claim 6,
Wherein the insulating layer is formed by selectively etching the current confined layer and then depositing AlOx or AlNx by ALD (atomic layer deposition).
The method of claim 6,
Wherein the insulating layer forms AlOx by selective oxidation of the current confined layer.
The method of claim 6,
The upper dielectric mirror layer is made of a material having a large difference in dielectric constant including SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si and CaF2 / ZnS, each having a thickness of 0.25x optical length (length divided by the refractive index at the center wavelength) Wherein the wavelength of the laser light is set to be 2 to 7 cycles in one cycle.
The method of claim 6,
The lower dielectric mirror layer is made of a material having a large difference in dielectric constant including SiOx / SiNx, SiOx / TiOx, CaF2 / a-Si and CaF2 / ZnS. Each of the lower dielectric mirror layers has a thickness of 0.25x (length divided by refractive index) Wherein the wavelength of the laser light is set to be 2 to 7 cycles in one cycle.
The method of claim 6,
Wherein the metal mirror layer is formed by depositing any one of Au, Al, and Ag.

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